Surface cleaning in any given environment is generally undertaken to maintain hygiene by removing residues left on the surface. Cleaning prevents contamination of substances, articles, and utensils as well as any other animate or inanimate objects such as food which may come in contact with the surface. While certain residues merely comprise carbonaceous debris, this debris may often provide a host or starting point for the growth of bacteria, microorganics, or other contaminants.
Additionally, surfaces may also be cleaned to maintain their serviceability and mechanical integrity during operation. In any given industrial or commercial setting, surfaces such as walls, floors, countertops, as well as, ranges, grills, ovens, mixing tanks, storage racks, and the like may all present difficult surfaces to clean and disinfect. Such structures may all, from time to time, contain surfaces which retain large residual contamination which is difficult to clean. Further, given the extended use that such equipment is subjected to, repeated cleaning is an ongoing problem. However, the frequency of such cleaning generally requires a high level of efficiency with minimal expenditure of human resources in the form of time and manpower.
For example, cleaners such as those useful in ovens often work by application to the intended surface for extended periods of time. Current industrial detergents designed to be foam applied are capable of producing large levels of foam. However, when applied to soiled or cleaned vertical surfaces, for example, the foam begins to sag, collapse, and move toward the floor within minutes of application. Soil removal is often incomplete due to the limited contact time of the foam. As a result, repeated applications of the cleaner is often necessary. Another problem associated with current foaming detergents is the drying of the foam on the surface prior to rinsing. Premature drying may also require another detergent application to solubilize the remaining detergent residues and, ultimately, produce a clean, streak-free surface.
A number of cleaners have been developed for industrial and institutional surfaces. Gel compositions have been developed to clean and overcome the limited contact time between the detergent and soil associated with foam cleaning. These products utilize thickening agents to increase product to soil contact time in an attempt to improve soil removal. However, gel cleaners have some of the same limitations as foam cleaners including drying of the solution, poor rinseability, and poor visibility of the product once applied.
Past attempts at cleaning compositions include Verboom, U.S. Pat. No. 4,477,365, which discloses the use of a composition containing an alkaline metal hydroxide, betaine, alpha olefin sulfonate, and hydrotropic agent. Schoenholz, U.S. Pat. No. 3,808,051 discloses a cleaning composition comprising an alkali metal salt of a weak organic acid, and a polyhydric alcohol which is used at a temperature of 250.degree.-550.degree. F. Eisen, U.S. Pat. No. 3,779,933 discloses a composition comprising an alkali metal hydroxide incorporating a nitrogen containing anionic surfactant, a thickening agent, and, optionally, a foam forming agent. Rink, U.S. Pat. No. 4,135,947 discloses a water-based composition having a pH of less than 10 and comprising carbon dioxide, neutralized amines, water soluble solvents, and thickening agents. Heile, U.S. Pat. No. 4,512,908 discloses an alkaline detergent composition comprising a chlorine source along with synthetic hectoright thickeners.
Generally, these prior compositions teach the use of alkaline cleaning constituents in a gelled or foaming state for use in applications such as ovens.
However, to date, these compositions have not been able to overcome problems including a lack of ease in rinseability, requirements for repeated application, and overall efficacy. As a result, a need exists for a alkaline stabilized foam for hard surface cleaning which provides the overall stability and cleaning requirements which allow application to any number of given surfaces.